Q. The freezing point of one modal $NaCl$ solution assuming NaCl to be 100 % dissociated in water is (modal depression constant=1.86)
A) $- 2.72℃$
B) $- 3.72℃$
C) $2.72℃$
D) $3.72℃$
Explanation
(b)
For $NaCl,i = 2$
$\mathrm{\Delta}T_{f} = 2k_{f} \times m = 2 \times 1.86 \times 1 = 3.72$
$T_{s} = T - \mathrm{\Delta}T_{f} = 0 - 3.72 = - 3.72℃$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.